Sanity checks are performed on includes and excludes in precious.toml

[rafl]

To address the same concern as the external tool https://github.com/oalders/ppath/.

When using the git version control system, this can be achieved reasonably fast with a combination of calls to git ls-files and git check-ignore, as illustrated by a prototype implementation I wrote (https://houseabsolute.slack.com/archives/C2M2EM0LX/p1670442201584039 if you're on this slack - ask for an invite if you're curious).

We want:

• there to exist a new command to check a precious config file for the issues ppath is trying to address
  • the new command to exit with a non-zero status when any issues are found
• these checks to be performed by default on every tidy/lint run
  • any violation of the checks to be merely a warning
  • the checks to be fast
    • it's OK to be VCS-specific and to not initially support all VCSs that precious aims to support

[oalders]

I'm not sure that git ls-files can easily be used to check the include/exclude patterns in the config.

The config appears to be using file glob patterns. git ls-files would be using gitignore matching patterns. There is some overlap here, but there are some significant differences as well.

[oschwald]

I believe ignore::gitignore is used for the exclude paths, which, as the name suggests, uses the gitignore glob format.